1. Field of the Invention
This invention relates to the field of handheld computers. In particular, the invention relates to managing a communications port of a handheld computer to help relieve power consumption and port contention.
2. Description of the Related Art
The management of communications port contention and power consumption affect the ease of use and the battery life of handheld computers. A typical handheld computer includes limited communications port resources. For example, the Palm V personal organizer has only one communications port available to interface with peripherals. When the communications port is exclusively occupied by a peripheral, the communications port is unavailable for other uses. For example, a handheld computer with an active keyboard occupying the communications port may be unable to perform an infrared data reception process with another handheld computer.
Another ease of use issue is the degree of user intervention required to manage a communications port. Requiring a user to manually open the communications port, for example through the graphical user interface or the buttons of the handheld computer, may be less preferable to automatically opening the communications port when the handheld computer receives information from a peripheral device. Further, requiring a user to explicitly close the communications port may be less preferable to automatically closing the communications port after the peripheral device and the handheld computer no longer exchange data. In one existing solution, the handheld computer will automatically close a communications channel, which was opened to work with a keyboard peripheral, when the handheld computer is prompted with a signal prompting a synchronization process, e.g. by a cradle for a HotSync™ process. However, if a user forgets to explicitly close the communications port after using a keyboard that occupied the communications port, the user may be unable to perform an infrared data reception process.
At best, the user is delayed with extra steps; at worst, the user may have the mistaken impression that the handheld computer has malfunctioned.
Requiring a user to manually close the communications port also affects power consumption. Battery powered systems, such as handheld computers, are sensitive to applications that drain excessive power. Thus, handheld computers mostly leave their communications ports in a low power standby mode. An open communications channel may consume significant power. For example, the Palm V personal organizer has a communications port included in the processor that is shared between an infrared communications port and an RS-232 serial communications port. The Palm V handheld organizer keeps these ports in standby to reduce power consumption. A user that forgets to close the communications port after a peripheral device is no longer used may suffer a significantly decreased battery life, and be forced to recharge or change batteries often.
Accordingly, what is needed is communications port management that eases port contention, helps conserve power, makes the handheld computer more user friendly, and accommodates multiple peripheral devices.